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1.
Micelle‐enhanced spectrofluorimetric method for quantification of entacapone in tablets and human plasma
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In this paper, a simple and highly sensitive spectrofluorimetric method was developed and validated for the determination of entacapone (ETC). The proposed method is based on forming a highly fluorescent product through the reduction of ETC with Zn/HCl. The produced fluorophore exhibits strong fluorescence at λem 345 nm after excitation at λex 240 nm. The use of fluorescence enhancers such as Tween‐80 and carboxy methyl cellulose (CMC) greatly enhanced the fluorescence of the produced fluorophore by 150% and 200%, respectively. Calibration curves showed good linear regression (r2 > 0.9998) within test ranges of 0.05–2.0 and 0.02–1.80 μg mL?1 with lower detection limits of 1.27 × 10?2 and 4.8 × 10?3 μg mL?1 and lower quantification limits of 4.21 × 10?2 and 1.61 × 10?2 μg mL?1 upon using Tween‐80 and or CMC, respectively. The method was successfully applied to the analysis of ETC in its pharmaceutical formulations (either alone or in presence of other co‐formulated drugs). The results were in good agreement with those obtained using the official method. The methods were further extended to determine the drug in human plasma samples, and to study the pharmacokinetics of ETC. The paper is the first report on the spectrofluorimetric determination of entacapone. 相似文献
2.
A chemiluminescent method using flow injection (FI) was investigated for rapid and sensitive determination of enalapril maleate and atenolol, which are used in the treatment of hypertension. The method is based on the sensitizing effect of these drugs on the Ce(IV)–sulfite reaction. The different experimental parameters affecting the chemiluminescence (CL) intensity were carefully studied and incorporated into the procedure. The method permitted the determination of 0.01–3.0 µg mL?1 of enalapril maleate in bulk form with correlation coefficient r = 0.99993, lower limit of detection (LOD) 0.0025 µg mL?1 (S/N = 2) and lower limit of quantitation (LOQ) 0.01 µg mL?1. The linearity range of atenolol in bulk form was 0.01–2.0 µg mL?1 (r = 0.99989) with LOD of 0.0003 µg mL?1 (S/N = 2) and LOQ of 0.01 µg mL?1. In biological fluids the linearity range of enalapril maleate was 0.1–2.0 µg mL?1 in both urine and serum, and for atenolol the linearity range was 0.1–1.0 µg mL?1 in both urine and serum. The method was also applied to the determination of the drugs in their pharmaceutical preparations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
3.
Chiral stationary phases are conveniently used for enantiomeric separation of drugs by liquid chromatography. Consumption of large volumes of hazardous solvents is considered as a common challenge for the sustainability of this technique. To this end, a columnar chromatography has been adopted using 50‐mm‐length stationary phases. The study comprised five Phenomenex Lux cellulose‐ and amylose‐based columns for the separation of guaifenesin (GUA) enantiomers. In addition, an experimental design was used to optimize the gradient profile for the separation of racemic GUA and ambroxol HCl (AMB) binary mixture. The chromatographic method was achieved using Lux Cellulose‐1 (50 × 4.6 mm) as a chiral stationary phase and ethanol/water as a mobile phase with linear gradient elution of 20% to 70% ethanol in 6 minutes at a flow rate of 1.0 mL min?1 and UV detection at 270 nm. Linearity ranges were found to be 50 to 1000 μg mL?1 and 15 to 450 μg mL?1 for each GUA enantiomer and AMB, respectively. Environmental, health and safety tool was used to assess and compare greenness of the proposed and reported methods. Short column indeed reduces the environmental impact by decreasing waste by about 60% and utilizing only 1‐mL ethanol in the mobile phase. The proposed method is a safer alternative for the simultaneous determination of drugs in their combined pharmaceutical formulation. The method has been validated and compared favorably with a reported one. 相似文献
4.
J. Yuan R.‐Q. Li Y. Shi X.‐Y. Peng X.‐X. Chen Z.‐X. Wu 《Zeitschrift fur angewandte Ichthyologie》2014,30(1):109-113
A pharmacokinetic study of oxytetracycline (OTC) following a single (100 mg kg?1) or a multi‐dose (100 mg kg?1 for 5 days) oral administration was carried out in yellow catfish, Pelteobagrus fulvidraco. After oral administration at 25°C, a one‐compartment model was developed. The absorption half‐life (t1/2(ka)) was 3.92, 1.44, 2.75, and 3.34 h in plasma, muscle, liver, and kidney after the single dose, and 0.35, 0.22, 0.42, 0.32 h after the multi‐dose, respectively. The order of peak concentration (Cmax) was liver > kidney > plasma > muscle, at 3.48 μg g?1, 2.90 μg g?1, 1.46 μg ml?1, and 1.39 μg g?1 after the single dose, and 14.02 μg g?1, 8.51 μg g?1, 4.17 μg ml?1, and 3.84 μg g?1 after the multi‐dose, respectively. The elimination half‐lives (t1/2(ke)) of OTC in plasma, muscle, liver, and kidney were calculated to be 7.64, 26.29, 19.08, and 10.61 h after the single dose, and 47.54, 70.99, 49.87, and 47.73 h after the multi‐dose, respectively. The results suggest that OTC was absorbed faster after the multi‐dose than after the single dose, suggesting that OTC could be more efficacious after the multi‐dose and more effective in the control bacterial diseases in aquaculture, with the side effects of longer withdrawal periods. 相似文献
5.
A comparison of isoprene and monoterpene emission rates from the perennial bioenergy crops short‐rotation coppice willow and Miscanthus and the annual arable crops wheat and oilseed rape
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Biogenic volatile organic compounds (BVOC) emissions from bioenergy crops may differ from those of conventional crops. We compared emission rates of isoprene and a number of monoterpenes from the lignocellulosic bioenergy crops short‐rotation coppice (SRC) willow and Miscanthus, with the conventional crops wheat and oilseed rape. BVOC emission rates were measured via dynamic vegetation enclosure and GC‐MS analysis approximately monthly between April 2010 and August 2012 at a location in England and from SRC willow at two locations in Scotland. The largest BVOC emission rates were measured from willow in England and varied between years. Isoprene emission rates varied between μg g?1 h?1. Of the monoterpenes detected from willow, α‐pinene emission rates were highest (μg g?1 h?1), followed by μg g?1 h?1 for δ‐3‐carene, μg g?1 h?1 for β‐pinene and μg g?1 h?1 for limonene. BVOC emission rates measured in Scotland were much lower. Low emission rates of isoprene and α‐pinene were measured from Miscanthus in 2010 (μg g?1 h?1 and μg g?1 h?1, respectively) but were not detected in subsequent years. Emission rates from wheat of isoprene were negligible but relatively high for monoterpenes (μg g?1 h?1 and μg g?1 h?1 for α‐pinene and limonene, respectively). No significant emission rates of BVOCs were measured from oilseed rape. The measured emission rates followed a clear seasonal trend. Crude extrapolations based solely on data gathered here indicate that isoprene emissions from willow could correspond to 0.004–0.03% (UK) and 0.76–5.5% (Europe) of current global isoprene if 50% of all land potentially available for bioenergy crops is planted with willow. 相似文献
6.
Spectrofluorimetric determination of certain adrenergic agonist drugs in their pure forms and pharmaceutical formulations: Content uniformity test application
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A new, simple, sensitive and rapid spectrofluorimetric method has been developed for determination of certain adrenergic agonists such as isoxsuprine hydrochloride, ritodrine hydrochloride and etilefrine hydrochloride in their pure forms and pharmaceutical dosage forms. The method depends on micellar enhancement of the native fluorescence of investigated drugs by using 2% w /v sodium dodecyl sulfate (SDS) as an anionic surfactant. The enhanced fluorescence intensity of investigated drugs was measured at 305 nm after excitation at 278 nm. The interaction of studied drugs with SDS was studied, and the enhanced fluorescence intensity was exploited to develop an assay method for the determination of investigated drugs. The relative fluorescence intensity–concentration plots were rectilinear over the range 0.15–3.00 μg ml?1, with low quantification limits of 0.132, 0.123 and 0.118 μg mL?1 for isoxsuprine, ritodrine and etilefrine, respectively. The proposed method was successfully applied for determination of studied drugs in their pharmaceutical formulations. Moreover, the high sensitivity of the proposed method allows performing the content uniformity testing of the studied drugs in their tablets by using the official United States Pharmacopeia (USP) guidelines. Statistical comparisons of the results with those of the reported methods revealed excellent agreement and indicated no significant difference in accuracy and precision. 相似文献
7.
Detection of metronidazole in honey and metronidazole tablets using carbon dots‐based sensor via the inner filter effect
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In this work, carbon dots (CDs) with a high quantum yield (22.3%) were easily prepared by hydrothermal pyrolysis of acid fuchsin 6B and hydrogen peroxide at 180°C for 10 h. The resultant CDs possess a narrow size distribution in the range of 2.6 to 3.2 nm and emit blue fluorescence. Interestingly, the absorption band of metronidazole (MTZ) centered at 318 nm can complementary overlap with the excitation band of the as‐prepared CDs centered at 320 nm, resulting in an inner filter effect (IFE) in high efficiency. In fact, the fluorescence quenching of the CDs depends on the concentration of MTZ. Therefore, a simple method for the detection of MTZ can be established using the CDs‐based sensor via the IFE. The linear range of the proposed method was 0–10 μg mL?1 with the limit of detection as low as 0.257 μg mL?1. This CDs‐based sensor had been applied for the detection of MTZ in honey and MTZ tablets with the recoveries in the range of 98.0% to 105.1% and 95.7% to 106.5%, respectively. Therefore, the as‐prepared CDs have a potential to be developed as a MTZ sensor with high selectivity, sensitivity and accuracy. 相似文献
8.
Supramolecular solvent‐based vortex‐mixed microextraction: Determination of chiral triazole fungicide in beer samples
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A supramolecular solvent composed of decanol in tetrahydrofuran/water was utilized for the simultaneous microextraction of chiral triadimefon and triadimenol in beer samples. Supramolecular solvents are nanostructured amphiphilic liquids that contain aqueous cavities, and the size of those cavities can be adjusted by the ratio of decanol, tetrahydrofuran, and water. The target analytes were mixed into the matrix sample and extracted in the supramolecular solvent phase, which was followed by separation and quantification by chiral liquid chromatography‐mass spectrometry. The influences of some analytical parameters and matrix components were all examined. Under the optimized conditions, the method detection limits were in the range of 0.24 to 0.98 μg L?1 (at a signal/noise of 3), with relative standard deviations between 1.6 and 5.7%. The linearities of the calibration plots were between 0.5 to 50 (triadimenol) and 1.0 to 100 μg L?1 (triadimefon). When this method was applied to a spiked beer sample, the recoveries ranged from 84 to 100%. 相似文献
9.
10.
Development of stability indicating HPLC method for the separation and validation of enantiomers of miconazole
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Nadia Bounoua Khaled Sekkoum Mehmet Gumustas Nasser Belboukhari Sibel A. Ozkan 《Chirality》2018,30(6):807-815
A selective and sensitive stability indicting HPLC method was developed for the analysis of enantiomers of miconazole. For this purpose, six different polysaccharide‐based chiral columns were evaluated. Optimization was performed using several polar organic and alcohol‐hydrocarbon mobile phases. As a result of optimization studies, the analysis was carried out using Lux Cellulose‐3, methanol as a mobile phase at a flow rate of 1 mL·min?1, and the detection wavelength was arranged to 230 nm. Developed method has been fully validated according to International Council on Harmonization guidelines. Method was found linear in the concentration range of 1 to 200 μg·mL?1. Coefficient of determination (R2) was calculated as 0.9996, intraday precision of the method was found with the RSD% of 0.56, and the recovery of the method was calculated close to 100%. Furthermore, some other validation parameters like specificity, selectivity, LOD, and LOQ were also investigated. Stability indicating capability of this method was shown by forced degradation studies, and the run time for each analysis was less than 6 minutes. As a result, simple, fast, reliable HPLC method was developed for the separation and determination of the enantiomers of miconazole. Applicability of the developed method was shown with the application of marketed pharmaceutical preparations. 相似文献
11.
A new system for the determination of nucleic acid by rare earth metallic porphyrin of [tetra‐(3‐methoxy‐4‐hydroxyphenyl)]–Tb3+ [T(3‐MO‐4HP)–Tb3+] porphyrin as fluorescence spectral probe has been developed in this paper. Nucleic acid can enhance the fluorescence intensity of the T(3‐MO‐4HP)–Tb3+ porphyrin in the presence of bis(2‐ethylhexyl)sulfosuccinate sodium salt(AOT) micelle. In pH 8.00 Tris–HCl buffer solution, under optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of nucleic acids in the range of 0.05–3.00 µg mL?1 for calf thymus DNA (ct DNA) and 0.03–4.80 µg mL?1 for fish sperm DNA(fs DNA). Their detection limits are 0.03 and 0.01 µg mL?1, respectively. In addition, the binding interaction mechanism between T(3‐MO‐4HP)–Tb3+ porphyrin and ct DNA is also investigated by resonance scattering and fluorescence spectra. The maximum binding number is calculated by molar ratio method. The new system can be used for the determination of nucleic acid in pig liver, yielding satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
Benzofurazan‐based fluorophore for the selective determination of flupentixol dihydrochloride: Application to content uniformity testing
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One of the most commonly used drugs in treatment of schizophrenia is flupentixol dihydrochloride, therefore it is important to develop a simple, low cost and sensitive spectrofluorimetric method for the estimation of flupentixol dihydrochloride. The yellow fluorescent product that is generated from the nucleophilic substitution reaction of the free lone pair of the alcoholic hydroxyl group of the drug and 4‐chloro‐7‐nitrobenzofurazan (NBD‐Cl) in Mcllvaine buffer pH 7.0 was estimated at 510 nm (λex 460 nm). The variables that affect the development of the reaction product were explored and optimized. The linear range of this method was 0.5–2.5 μg ml?1 with a limit of quantitation equal to 0.29 μg ml?1. Our method was successfully applied for the assurance of flupentixol in tablet form with average percentage recovery of 99.08 ± 1.01% without obstruction from the basic excipients exhibits. Furthermore, our strategy was extended to study the content uniformity testing of flupentixol in Fluaxnol® tablets. 相似文献
13.
Juan José Dorantes‐Aranda Peter D. Nichols Trevor David Waite Gustaaf M. Hallegraeff 《Journal of phycology》2013,49(2):427-438
Lipid profiles of three strains (Mexico, Australia, Japan) of Chattonella marina (Subrahmanyan) Hara et Chihara were studied under defined growth (phosphate, light, and growth phase) and harvest (intact and ruptured cells) conditions. Triacylglycerol levels were always <2%, sterols <7%, free fatty acids varied between 2 and 33%, and polar lipids were the most abundant lipid class (>51% of total lipids). The major fatty acids in C. marina were palmitic (16:0), eicosapentaenoic (EPA, 20:5ω3), octadecatetraenoic (18:4ω3), myristic (14:0), and palmitoleic (16:1ω7c) acids. Higher levels of EPA were found in ruptured cells (21.4–29.4%) compared to intact cells (8.5–25.3%). In general, Japanese N‐118 C. marina was the highest producer of EPA (14.3–29.4%), and Mexican CMCV‐1 the lowest producer (7.9–27.1%). Algal cultures, free fatty acids from C. marina, and the two aldehydes 2E,4E‐decadienal and 2E,4E‐heptadienal (suspected fatty acid‐derived products) were tested against the rainbow trout fish gill cell line RTgill‐W1. The configuration of fatty acids plays an important role in ichthyotoxicity. Free fatty acid fractions, obtained by base saponification of total lipids from C. marina showed a potent toxicity toward gill cells (median lethal concentration, LC50 (at 1 h) of 0.44 μg · mL?1 in light conditions, with a complete loss of viability at >3.2 μg · mL?1). Live cultures of Mexican C. marina were less toxic than Japanese and Australian strains. This difference could be related to differing EPA content, superoxide anion production, and cell fragility. The aldehydes 2E,4E‐decadienal and 2E,4E‐heptadienal also showed high impact on gill cell viability, with LC50 (at 1 h) of 0.34 and 0.36 μg · mL?1, respectively. Superoxide anion production was highest in Australian strain CMPL01, followed by Japanese N‐118 and Mexican CMCV‐1 strains. Ruptured cells showed higher production of superoxide anion compared to intact cells (e.g., 19 vs. 9.5 pmol · cell?1 · hr?1 for CMPL01, respectively). Our results indicate that C. marina is more ichthyotoxic after cell disruption and when switching from dark to light conditions, possibly associated with a higher production of superoxide anion and EPA, which may be quickly oxidized to produce more toxic derivates, such as aldehydes. 相似文献
14.
Fluorescence‐based sensor for selective and sensitive detection of amoxicillin (Amox) in aqueous medium: Application to pharmaceutical and biomedical analysis
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Samadhan P. Pawar Laxman S. Walekar Dattatray B. Gunjal Dattatray K. Dalavi Anil H. Gore Prashant V. Anbhule Shivajirao R. Patil Govind B. Kolekar 《Luminescence》2017,32(6):918-923
We here for the first time demonstrate an analytical approach for the highly selective and sensitive detection of amoxicillin (Amox) in aqueous medium based on the fluorescence quenching of quantum dots (QDs). The change in fluorescence intensity of mercaptopropionic acid‐capped cadmium sulphide (MPA‐CdS) QDs is attributed to the increasing concentration of Amox. The results show that the fluorescence quenching of QDs by Amox takes place through both static and dynamic types of quenching mechanism. The fluorescence quenching of QDs with increase in concentration of Amox shows the linear range between 5 μg ml?1 and 30 μg ml?1 and the limit of detection (LOD) is 5.19 μg ml?1. There is no interference of excipients, which are commonly present in pharmaceutical formulation and urine samples. For the practical application approach, the developed method has been successfully applied for the determination of Amox in pharmaceutical formulations and urine samples with acceptable results. 相似文献
15.
A series of amphiphilic diblock copolypeptides (K30‐b ‐F15, K30‐b ‐F30, and K30‐b ‐F45) were synthesized via N ‐carboxy‐α‐amino‐anhydride ring‐opening polymerization. The copolypeptides had excellent antibacterial efficacy to both Gram positive (S. aureus ) and Gram negative (E. coli ) bacteria. The minimum inhibitory concentrations (MICs) against E. coli and S. aureus are 8 μg mL?1 and 2 μg mL?1, respectively, lower than most natural and artificial antimicrobial peptides (AMPs). The morphological changes of the bacteria treated with diblock copolypeptides were investigated by transmission electron microscopy; the results proved that the diblock copolypeptides had a similar antibacterial pore‐forming mechanism to natural cationic peptides. This was confirmed by laser scanning confocal microscope images. CCK‐8 results and the MICs showed that the diblock copolypeptides have high selectivity to bacteria, which suggested that the diblock copolypeptides could be excellent candidates to replace traditional antibiotics in future. 相似文献
16.
Toxicity,behavior impairment,and repellence of essential oils from pepper‐rosmarin and patchouli to termites
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Leandro Bacci Janaína K.A. Lima Ana Paula A. Araújo Arie F. Blank Indira M.A. Silva Abraão A. Santos Ane C.C. Santos Péricles B. Alves Marcelo C. Picanço 《Entomologia Experimentalis et Applicata》2015,156(1):66-76
Plant essential oils are potential sources of insecticidal compounds, but have rarely been explored for their effect on termites. In the present study, we assessed the chemical composition of essential oils of Lippia sidoides Cham. (pepper‐rosmarin; Verbenaceae) and Pogostemon cablin (Blanco) Benth. (patchouli; Lamiacaeae) and evaluated their toxicity, behavioral impairment, and repellence to termite species of the genera Amitermes and Microcerotermes (Isoptera: Termitidae: Termitinae). The main components of essential oils of L. sidoides and P. cablin were thymol (44.6%) and patchouli alcohol (36.6%), respectively. The essential oil of P. cablin was most potent against Amitermes cf. amifer Silvestri and had the lowest LD50 (0.63 μg mg?1). There was no difference in toxicity for Microcerotermes indistinctus Mathews between the essential oils of L. sidoides (LD50 = 1.49 μg mg?1) and P. cablin (LD50 = 1.67 μg mg?1). Pogostemon cablin essential oil was the most toxic to M. indistinctus (LC50 = 0.32 μl ml?1) and A. cf. amifer (LC50 = 0.29 μl ml?1). The essential oils analyzed exhibited high toxicity and repellence to the termites, in addition to reducing behavioral interactions among individuals, thus constituting potential termiticides. 相似文献
17.
A high‐performance liquid chromatography (HPLC) method was established to detect Xeljanz enantiomers in active pharmaceutical ingredients (APIs) and tablets. The separation was achieved on a Chiralpak IC column using a mobile phase of hexane‐ethanol‐diethylamine (65:35:0.1, v/v). The detection wavelength was 289 nm. The peak areas and the enantiomer concentrations in the range of 0.15–2.25 μg?mL?1 were in high linearity, with correlation coefficients higher than 0.999. The recoveries were 86.44% at the concentrations of 7.5, 18.75, and 37.5 μg?mL?1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.042 and 0.14 μg?mL?1, respectively. This HPLC method is suitable for detecting the enantiomers of Xeljanz in its APIs and tablets. Chirality 27:235–238, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
18.
Investigation of the binding of AuNPs–6‐mercaptopurine and the sensitive detection of 6‐mercaptopurine using resonance Rayleigh light scattering
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A highly sensitive method for the detection of 6‐mercaptopurine (MP) by resonance Rayleigh light scattering (RLS) method was developed. Gold nanoparticles (AuNPs) were synthesized by a modified seed method and characterized using transmission electron microscopy (TEM). AuNPs were bound to MP via covalent bonding to form the MP–AuNPs complex, which increased the RLS intensity of MP at 347 nm (increased by 65.7%). Under optimum conditions, the magnitude of the enhanced RLS intensity for MP–AuNPs was proportional to MP concentration in the range 0.0681–1.702 μg mL?1. The linear regression equation was represented as follows: ΔI RLS = 9.31 + 82.42c (r = 0.9948). The limit of detection (LOD, 3σ) was 3.32 ng mL?1. The system was applied successfully to detect MP in pharmaceuticals. MP recoveries were 99.9–101.7% with a relative standard deviation (RSD) (n = 5) of 0.59–0.77% for three synthetic samples, and 97.5–110.0% with an RSD of 0.98–2.10% (n = 5) for tablet samples. 相似文献
19.
Puja Kumari Ravindra Pal Singh A. J. Bijo C. R. K. Reddy Bhavanath Jha 《Journal of phycology》2012,48(6):1362-1373
The incipient levels of lipid hydroperoxides (LHPOs) were determined in selected green, brown, and red macroalgae by the FOX assay using hydroperoxy HPLC mix. The LHPOs contents varied between the investigated species and showed relatively low values in this study. Among the greens, it varied from 12 ± 6.2 μg · g?1 (Codium sursum) to 31.5 ± 2.8 μg · g?1 (Ulva lactuca), whereas in reds, from 5.7 ± 1.6 μg · g?1 (Gracilaria corticata) to 46.2 ± 6 μg · g?1 (Sarconema filiforme), and in browns, from 4.6 ± 4.4 μg · g?1 (Dictyota bartayresiana) to 79 ± 5.0 μg · g?1 (Sargassum tenerrimum), on fresh weight basis. These hydroperoxides represented a minor fraction of total lipids and ranged from 0.04% (S. swartzii) to 1.1% (S. tenerrimum) despite being a rich source of highly unsaturated fatty acids. The susceptibility of peroxidation was assessed by specific lipid peroxidazibility (SLP) values for macroalgal tissues. The LHPO values were found to be independent of both the PUFAs contents and their degree of unsaturation (DBI), as evident from the PCA analysis. SLP values were positively correlated with the LHPOs and negatively with DBI. The FOX assay gave ≥20‐fold higher values for LHPOs as compared to the TBARS method for all the samples investigated in this study. Furthermore, U. lactuca cultured in artificial seawater (ASW) enriched with nutrients (N, P, and NP) showed a sharp decline in LHPOs contents relative to those cultured in ASW alone P ≤ 0.05. It is inferred from this study that the FOX assay is an efficient, rapid, sensitive, and inexpensive technique for detecting the incipient lipid peroxidation in macroalgal tissues. 相似文献
20.
Synthesis and Antileishmanial Activity of Natural Dehydrodieugenol and Its Mono‐ and Dimethyl Ethers
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Luis Cezar Rodrigues José Maria Barbosa‐Filho Marcia Rosa de Oliveira Patrícia Lima do Nascimento Néris Flávio Valadares Pereira Borges Roberto Mioso 《化学与生物多样性》2016,13(7):870-874
The study of chemistry of naturally occurring compounds and the synthesis of their derivatives is fundamentally important for the development of new drugs. In this work, dehydrodieugenol (DHDE) was obtained through oxidative coupling of eugenol, promoted by an aqueous mixture of potassium ferricyanide (K3[Fe(CN)6]) and NH3 · H2O. The partial methoxylation of DHDE with MeI and K2CO3 mainly resulted in the molecular‐shaped monomethyl ether (DHDE‐1MeO) and its dimethyl ether derivative (DHDE‐2MeO). The products from the reactions were characterized by 1H‐ and 13C‐NMR spectroscopy. Additionally, these studies have reported the antileishmanial activity of DHDE against Leishmania amazonensis (IC50 value of 42.20 μg ml?1) and shown that partial methoxylation of DHDE results in a significant increase in its antiparasitic activity (IC50 value of 13.68 μg ml?1). Based on in vitro bioassays, DHDE‐1MeO has shown the highest leishmanicidal activity in promastigota form. Production by direct one‐step synthesis of this monomethoxylated compound can be considered to be a cost‐effective and environmentally friendly method with a short reaction time. 相似文献